Rotary pumps



April 17, 1962 o, MA|5CH ROTARY PUMPS original Filed March 13. 195e mnu Zin/afan 3,029,740 ROTARY PUMPS onv'r Marsch, chicago, nl., assigner to nahm Pump Company, Chicago, Ill., a corporation of Illinois Original application Mar. 13, 1956, Ser. No. 571,251, now

Patent No. 2,909,124, dated Oct. 20, 1959. Divided and this application Apr. 29, 1959, Ser. No. 809,802

, A 1 Claim. (Cl. 10S-126) y This application is a division of my copending application Serial No. 571,251 led March 13, 1956, now Patent No. 2,909,124.

This invention relates to small motor driven pumps and has for its object to produce a simple and inexpensive pumpwhich can be cleaned quickly and easily so as to be kept in a thoroughly sanitary condition; thus guarding against contamination of liquids handled thereby, and the invention relates particularly to check valve, structures adapted for use insuch pumps and which may be readily disassembled and reassembled for cleaning purposes.

Asidel 4from using in the construction of a pump materials -that vare'not harmfulto liquids passing through the same, one of the most important factors is the ability to dismantlethe same so completely that every surface that touches the liquids can readily be exposed. -This may beV made possible through so constructing the pump that it may be completely dismantled and again assembled.

One of the objects ofthe invention s therefore to create such a structure that dismantling and assembling may be done entirely by hand, without reliance on tools.

The various features of novelty whereby the invention `is characterized will hereinafter be pointed out in the claim; but, for a full understanding ofthe invention and -only the pump, proper;

FIG. 5 is a section through the pump, on the same scale as FIG. 3, on line 5-5 of FIG. l; and

ice

ing ring 18, preferably in the form of an endless annular trough; the open side of the trough facing the pump chamber. This packing ring forms an effective seal around shaft and against disc or plate 3 to close the only outlet through the rear or bottom of the'pump chamber.

In the face of disc 2 that engages disc 1 is an annular groove 19 encircling the pump chamber. In this groove is an elastic packing ring 20 which forms a seal between these two discs.

In openings 5 and 6 are xed corresponding ends of r nipples 21 and 22, respectively. Tubes 23 may be at- FIG. 6 is a view similar to FIG. 4 with the gears and l sealing ring omitted.

Referring to FIGS. 1-6 of the drawings, 1 and 2 are plate; disc 2 lying between discs 1 and 3. Disc 2 is shown as being thicker than the other two discs so that it may be deeply recessed in the face in contact with disc 1 to create the pump chamber 4 of which the latter disc forms the cover. This pump chamber is of the conventional gear pump type, comprising two overlapping sections 4a and 4b. Disc 1contains two openings, 5 and 6, which are respectively, the inlet and outlet for the gear chamber. l

In chamber 4'are two gears 7 and 8. Gear 7 is-mounted for rotation about a little stub shaft 9 rising from the bottom of said chamber and extending almost to disc 1. Gear 8 surrounds a shaft 10 that extends into the pump housing through an opening 11 in disc 3 and an opening 12 in disc 2 in registration with the latter opening. Openings 11 and 12 are so designed that there is formed between disc 3 and the pump chamber a pocket 12.a partially closed at the ends by discs 2 and 3.

Shaft 10 is provided with a radial pin 14 that fits slidably in a groove 15 opening into the axial bore 16 in gear 8. Shaft 10 is pinned to motor shaft 17 so as to rotate therewith. Fitting in pocket 12a is an elastic packtached to these nipples when the pump is in use. In the absence of 'such tubes, caps 24 may be snapped over the ends of the nipples to keep out foreign matter.

The outlet nipple 22 is a check valve. This consists of a ball 25 cooperating with a valve seat on the inner end of a shortlsleeve or bushing 2,6 frictionally held in the inner end of the nipple.` The grip ofthe sleeve is increased by` Van elasticv packing ring 27 fitted into an external circumferentialgroove in the sleeve. The ball is normally held against the seat by a spring 13.

The entire pump assembly is clamped together and to an adapter 30 mounted on the casing of a motor by two screws 32 having wing heads 33. Each screw is also provided with an integral collar 34 which bears against the outer face of disc 1 when the screws are tightened. The

`holes in the three discs through which the screws pass are simple bores so that, once the screws are freed from the adapter, the entire pump comes apart; only shaft 10 remaining attached to the motor. Since pin 35, which secures shaft 10 to the motor shaft, is removable shaft 10 may be detached from the motor shaft forA cleaning or other purposes.

It will be noted that the pump is eccentrically mounted with respect to the motor shaft. To ensure that the discs can be assembled onlyin the proper angular positions relative to each other and the adapter, the latter is provided with a pair of short dowel pins 36 that project from the face thereof far enough to pass through holes 37 in disc 3 andinto registering holes 38 in disc 2. Disc 3 can be applied in only one way, namely, with opening 11 registering with opening 12 in disc 2 and with shaft 10. The identifying words Out and In, adjacent to the outlet nipple and the inlet nipple respectively, aid the assembler in applying disc 1, knowing that the outlet must be at the left or, more certainly, that the words must not be upside down. Pins 36 also serve accurately to align the pump withthe motor shaft, making it unnecessary for the screws 32 to perform that duty.

After the pump is detached from the motor the two gears may be caused to drop out by simply turning disc 2 over to bring the gears on the under side, and sealing members 18 and 20 may easily be detached. Also,` the 'Y inner end 26a ofl bushing or sleeve 26 in outlet nipple V22 is preferably so shaped that this element may be lifted out with ones fingers to permit the ball valve and spring to spill from the nipple.

It will thus be seen that the pump may quickly be so completely separated into its individual elements thatV f is therefore well adapted to pump liquids in small quantities even a drop at a time.

While I have illustrated anddescribed with particulary ity Vonly a single form of my invention, I do not desire to the like and having a main housing section with a pump chamber in one face thereof, meshingpump gears disposed removably in the chamber, a housing cover'secured in a quick detachable relation on said main section across said pump chamber, and inlet and outlet nipples fixed at their inner ends in and opening through said cover into the pump chamber to provide inlet and outlet passages for the pump chamber, the improvement which comprises an elongated expansive coil spring removably disposed Within said outlet nipple and having an outer end seated in said outlet nipple near the outer end of such nipple, a ball removably disposed within said outlet nipple and engaged by and urged inwardly of such nipple" by said spring, a short thick-walled sleeve removably fitted into the inner end of said outlet nipple and having a valve seat on its outer end engaged by said ball, said sleeve having an external groove extending around-the same, an elastic ring disposed in said groove and engaging the inside of the outlet nipple to hold the sleeve removably in position in the 4 nipple, and said sleeve having a second groove thereabout in an exposed location adjacent the inner end of the sleeve to provide an annular handle for engagement to remove the sleeve and release the ball and the spring for individual cleaning ofthe ball, the spring, the sleeve and the inner Y surfaces of the nipple. t f

References Cited the file of this patent UNITED STATES `ljyfllqls s 690,046 Bickel et al. 1-; Dec.Y 31, 1906 1,443,016 Eubanks Jan. 23, 1923 1,735,230 Brand Nov. 12, 1929 2,069,153 Konkle Jan. 26, 1937 2,451,586 Strid Oct. 19, 1948 2,489,787 Knowlton NOV. 29, 1949 2,619,039 Maisch Nov. 25, 1952 2,628,571 Neilsen Feb. 17, 1953 2,657,833 Steczynski et al Nov. 3, 1953 FOREIGN PATENTS 467,156 Great Britain June 11, 1937 588,153 GreatBritain @1 May 15, 1947 1,021,219 ,Germany f Dec.19, 1957 (GermanapplicationKL147g8) 

